JP5838307B2 - Hermetic rotary compressor - Google Patents

Description

  The present invention relates to a hermetic rotary compressor in which an electric element and a rotary compression element are housed in a hermetic container.

  Conventionally, this type of hermetic rotary compressor is configured such that an electric element (motor) and a rotary compression element that is rotationally driven by a rotating shaft of the electric element are housed in an airtight container. In the case of a vertical compression element, this rotary compression element is usually a cylinder that forms a compression chamber inside, a roller that is fitted in an eccentric part provided on the rotary shaft and rotates eccentrically in the cylinder, and abutting against the roller in the cylinder. Are divided into a low pressure chamber side and a high pressure chamber side, and an upper support member and a lower support member that close the upper and lower opening surfaces of the cylinder and have a bearing of a rotating shaft.

  Further, a cup is fixed with bolts on the upper surface of the upper support member on the electric element side, and a discharge muffler chamber (muffler) is formed between the cup and the upper surface of the upper support member. The bearing penetrates the cup and rises up from the upper surface of the upper support member, and the discharge silencer chamber is formed around the bearing. And the refrigerant | coolant compressed in the cylinder by the effect | action of eccentric rotation of a roller and a vane is set as the structure discharged to a discharge silencer chamber (for example, refer patent document 1).

  In this case, the hermetic rotary compressor becomes hot due to the operation of the electric element and the compression action of the refrigerant in the rotary compression element. If this temperature rises abnormally, failure of the electric element, seizure of the sliding part, etc. will occur. Therefore, a desuperheater is used in which the refrigerant discharged into the discharge silencer chamber is once cooled outside and then returned to the sealed container to cool the hermetic rotary compressor (see, for example, Patent Document 2).

Japanese Patent Laid-Open No. 9-151889 Japanese Patent Laid-Open No. 8-159568

  This desuperheater is connected to the outlet pipe and return pipe for the desuperheater attached to the sealed container, and the high-temperature refrigerant discharged into the discharge muffler chamber flows out of this outlet pipe and is cooled by the desuperheater. After that, it is returned to the sealed container from the return pipe. Since the temperature of the refrigerant returned to the hermetic container is lowered, the temperature of the electric element and the rotary compression element can be lowered. Then, the refrigerant is finally discharged from a refrigerant discharge pipe attached to the sealed container to a heat exchanger such as an external condenser or a gas cooler. Therefore, the refrigerant leaks directly into the sealed container without going from the discharge silencer chamber to the desuperheater, and when the amount increases, cooling in the sealed container is hindered.

  On the other hand, the inner edge of the cup is in contact with the bearing of the upper support member. In order to prevent the refrigerant from leaking from this portion, conventionally, a step portion is formed on the bearing, and the step portion is used for sealing. A ring was attached and the cup was in contact with this ring. As a result, the number of parts increases and the cost increases, and if forgetting to insert the ring occurs during manufacturing, there is a problem that the product becomes defective and cannot be used.

  The present invention has been made to solve the conventional technical problems, and an object thereof is to provide a hermetic rotary compressor that can seal between a cup and a bearing without using a ring or the like. It is what.

  In order to solve the above-described problems, a hermetic rotary compressor according to the present invention houses an electric element and a rotary compression element driven by the rotary shaft of the electric element in a hermetic container. After the compressed refrigerant is discharged into the discharge silencer chamber, the refrigerant flows into an external desuperheater, cooled by the desuperheater, returned to the sealed container, and from the refrigerant discharge pipe attached to the sealed container A discharge member, which has a bearing for the rotary shaft on one side and which constitutes a rotary compression element, and is fixed to one side of the support member with a bolt so that the bearing penetrates, and a support member around the bearing And a cup that forms a discharge silencing chamber between the support member and the support member. The bearing has a stepped portion, and the corner of the stepped portion is chamfered to form a chamfered portion, and the inner edge of the cup. Is curved with a predetermined curvature A bending portion is configured, and the bending portion abuts the chamfered portion of the step portion, and the bolt fixing portion of the cup before being fixed to the support member with the bolt in a state where the bending portion is in contact with the step portion is The dimensional relationship is such that it is spaced apart from the support member.

  The hermetic rotary compressor according to the second aspect of the present invention is such that when the radius of curvature of the curved portion of the cup is R, the thickness dimension of the cup is t, and the protruding dimension of the stepped portion is W, t <R <10 * It is characterized by W.

  According to the present invention, the electric element and the rotary compression element driven by the rotary shaft of the electric element are housed in the sealed container, and the refrigerant compressed by the rotary compression element is discharged into the discharge silencer chamber. Then, after flowing into an external desuperheater, cooling with this desuperheater, returning to the inside of the hermetic container, in the hermetic rotary compressor that discharges from the refrigerant discharge pipe attached to this hermetic container, A support member that has a bearing on one surface and constitutes a rotary compression element, and is fixed to one surface of the support member with a bolt so that the bearing penetrates, and covers the one surface of the support member around the bearing and between the support member And a cup that constitutes a discharge silencing chamber, a step is provided on the bearing, the corner of the step is chamfered to form a chamfered portion, and the inner edge of the cup is bent with a predetermined curvature to form a curved portion. Configure this curved part Dimensional relation that the bolt fixing part of the cup before being fixed to the support member with the bolt is separated from the support member with the chamfered part of the step part and the curved part being in contact with the step part. Therefore, by fixing the bolt fixing portion of the cup to the support member with the bolt, the curved portion of the cup comes into pressure contact with the chamfered portion of the stepped portion of the bearing.

  The pressure contact between the curved portion of the cup and the chamfered portion of the stepped portion significantly improves the sealability between the bearing and the cup, and the refrigerant can be discharged from the discharge silencer chamber into the sealed container without using a separate part such as a ring. Leakage can be effectively prevented or reduced. This makes it possible to reduce costs and reduce the defective rate during production while ensuring reliability.

  Further, by not using a separate part such as a ring, it is possible to make the tolerance in the height direction of the stepped portion only a bearing, and the amount of variation when the refrigerant leaks between the chamfered portion and the curved portion is reduced. . Furthermore, since the pressing force of the curved portion of the cup against the chamfered portion can be made constant over the entire circumference of the inner edge portion of the cup, there is an effect that variation in distortion of the end surface of the bearing is reduced.

  Further, when the radius of curvature of the curved portion of the cup is R, the thickness dimension of the cup is t, and the projecting dimension of the stepped portion is W as in the invention of claim 2, if t <R <10 * W. It is possible to reliably maintain the sealing performance between the chamfered portion of the stepped portion and the curved portion of the cup.

It is a vertical side view of a hermetic rotary compressor as an embodiment to which the present invention is applied. FIG. 2 is a longitudinal side view of a state in which a cup is fixed to an upper support member of the hermetic rotary compressor of FIG. 1. It is a vertical side view of the upper support member of the hermetic rotary compressor of FIG. It is an expansion vertical side view of the level | step-difference part part of the bearing of the upper support member of FIG. It is a vertical side view of the cup of FIG. FIG. 2 is an enlarged vertical side view of a step portion in a state where a cup is fixed to an upper support member of the hermetic rotary compressor of FIG. 1. It is a vertical side view of the state before fixing a cup with a volt | bolt to the upper support member of the hermetic rotary compressor of FIG. It is a figure explaining the dimension of the curvature radius of the curved part of the cup of the sealed rotary compressor of FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The hermetic rotary compressor 1 according to the embodiment houses an electric element 4 in an upper part of an internal space of a vertical cylindrical hermetic container 2 made of a steel plate, and is driven to rotate by a rotating shaft 8 of the electric element 4 in a lower part. This is a rotary compressor that houses the rotary compression element 3.

  The sealed container 2 includes a container body 2A that houses the electric element 4 and the rotary compression element 3, and a substantially bowl-shaped end cap (lid body) 2B that closes the upper opening of the container body 2A. On the upper surface of the end cap 2B, a terminal (wiring is omitted) 6 for supplying electric power to an electric element (motor) 4 positioned above the sealed container 2 is attached. Further, a refrigerant discharge pipe 7 communicating with the inside of the sealed container 2 is attached to the end cap 2B. The refrigerant discharge pipe 7 is connected to an external heat exchanger of a refrigerant circuit such as a condenser and a gas cooler (not shown). The space in the bottom of the sealed container 2 is an oil reservoir 9 in which oil for lubricating sliding portions such as the rotary compression element 3 and the rotating shaft 8 of the electric element 4 is stored.

  The rotary compression element 3 includes a cylinder 12, a roller 14 that is fitted in an eccentric portion 13 provided in the rotary shaft 8 in the cylinder 12 and rotates eccentrically in the cylinder 12, and a low pressure in the cylinder 12 by contacting the roller 14. A vane (not shown) that is divided into a chamber side and a high pressure chamber side, and an upper portion as a supporting member that closes the upper opening surface and the lower opening surface of the cylinder 12 and has an upper bearing 16A and a lower bearing 17A of the rotating shaft 8, respectively. The support member 16 and the lower support member 17 are configured. The upper bearing 16A protrudes from the center of the upper support member 16 in the direction of the upper electric element 4, and the lower bearing 17A protrudes downward from the center of the lower support member 17.

  The cylinder 12 is formed with a suction passage 18 communicating with the compression chamber inside the cylinder 12. Further, a discharge silencer chamber 19 is configured on the electric element 4 side (upper surface) of the upper support member 16. The discharge silencing chamber 19 on the upper surface of the upper support member 16 is a substantially bowl-shaped cup 21 having a central hole 21A through which the rotary shaft 8 and the upper bearing 16A of the upper support member 16 penetrate at the center (upper surface of the upper support member 16 ( The upper surface of the upper bearing 16A is formed between the cup 21 and the upper support member 16 around the upper bearing 16A. The cup 21, the upper support member 16, the cylinder 12, and the lower support member 17 are integrated by bolts 20 passing through them, and the rotary compression element 3 is assembled.

  The cup 21 may be fixed to the upper support member 16 with a bolt 20 that integrates the rotary compression element 3, or only the cup 21 may be fixed to the upper support member 16 with a different bolt. The cup 21 will be described in detail later.

  The discharge silencer chamber 19 and the high pressure chamber side in the cylinder 12 are communicated with each other by a discharge port 22 formed in the upper support member 16. A discharge valve (not shown) is provided on the discharge silencer chamber 19 side of the discharge port 22, and a discharge passage 23 formed in the cylinder 12 and a discharge silencer chamber are provided in the upper support member 16 farthest from the discharge port 22. A communication path 24 that communicates with 19 is formed.

  An outlet pipe 26 and a return pipe 27 for a desuperheater are attached to the container main body 2A of the sealed container 2, and the discharge passage 23 of the cylinder 12 communicates with the outlet pipe 26. An external desuperheater (not shown) is connected to the outlet pipe 26 and the return pipe 27, and the desuperheater is air-cooled by ventilation. The return pipe 27 communicates with the sealed container 12 between the rotary compression element 3 and the electric element 4.

  On the other hand, the electric element 4 includes a stator (stator) 31 that is welded and fixed in an annular shape along the inner peripheral surface of the upper space of the sealed container 2, and a rotor that is rotatably inserted by a magnetic field generated by the stator 31. (Rotor) 32, and the rotary shaft 8 is fixed to the rotor 32.

  A refrigerant introduction pipe 33 for introducing a refrigerant into the cylinder 12 is attached to the container body 2A of the sealed container 2, and one end of the refrigerant introduction pipe 33 communicates with the suction passage 18 of the cylinder 12. The other end of the refrigerant introduction pipe 33 opens at the upper part in the accumulator 34.

  With the above configuration, the operation of the hermetic rotary compressor 1 of the embodiment will be described. When the coil of the stator 31 of the electric element 4 is energized through the terminal 6 and a wiring (not shown), the electric element 4 is activated and the rotor 32 rotates. By this rotation, the roller 14 fitted to the eccentric portion 13 provided integrally with the rotating shaft 8 rotates eccentrically in the cylinder 12.

  Thus, the low-pressure refrigerant gas is sucked into the low-pressure chamber side of the cylinder 12 of the rotary compression element 3 through the accumulator 34, the refrigerant introduction pipe 33, and the suction passage 18. The refrigerant gas sucked into the low-pressure chamber side of the cylinder 12 is compressed by the operation of the roller 14 and a vane (not shown) to become a high-temperature and high-pressure refrigerant gas from the high-pressure chamber side of the cylinder 12 to the discharge silencer chamber 19 through the discharge port 22. Discharged.

  The refrigerant gas discharged into the discharge silencer chamber 19 passes through the interior, reaches the communication path 24, and flows into the desuper heater (not shown) from the outlet pipe 26 via the discharge path 23. The high temperature and high pressure refrigerant gas is air-cooled by the desuperheater, and the temperature is lowered. The refrigerant gas that has passed through the desuperheater returns from the return pipe 27 to the hermetic rotary compressor 1 and flows into the hermetic container 12. Then, the electric element 4 rises between the stator 31 and the container body 2A, between the stator 31 and the rotor 32, and through the rotor 32, and is discharged to the outside from the refrigerant discharge pipe 7 attached to the end cap 2B. Is done. When the refrigerant gas that has passed through the desuperheater passes through the sealed container 2, the electric element 4 and the rotary compression element 3 in the sealed container 2 are cooled, and the temperature rise is suppressed.

  Next, the attachment structure of the cup 21 will be described with reference to FIGS. A step portion 41 is formed around the upper bearing 16A rising from the center of the upper support member 16 at a position of a predetermined height dimension H1 from the upper surface of the upper support member 16 (FIG. 3). The corner of the stepped portion 41 is chamfered obliquely to form a chamfered portion 41A (FIG. 4). Further, a bolt hole 42 through which the bolt 20 described above is inserted is formed in a predetermined portion outside the upper bearing 16A.

  On the other hand, the cup 21 has a substantially bowl shape provided with the center hole 21A at the center and opened downward, and a flange portion 43 for fitting to the outer peripheral portion of the upper support member 16 is formed on the outer edge portion. Furthermore, the position corresponding to the bolt hole 42 of the upper support member 16 is partially formed in a stepped lower shape, and a bolt fixing portion 44 is formed in the lower portion, and the bolt 20 is inserted into the bolt fixing portion 44. Bolt holes 46 are formed.

  Further, the inner edge that borders the periphery of the center hole 21A is bent upward (in the direction in which the upper bearing 16A stands) with a predetermined curvature, and a curved portion 47 is formed there. Further, the height dimension H2 from the lower surface of the bolt fixing portion 44 (the surface on the upper support member 16 side) to the lower end where the inner surface of the bending portion 47 (the surface opposite to the center of the curved arc) ends (FIG. 5) is It is set smaller than the height dimension H1 of the stepped portion 41 (H2 <H1).

  When the cup 21 is put on the upper support member 16 in such a manner that the upper bearing 16A of the upper support member 16 is inserted into the center hole 21A of the cup 21 from below, the curved portion 47 of the inner edge of the cup 21 is eventually formed. The lower end of the inner surface contacts the chamfered portion 41A of the stepped portion 41 of the upper bearing 16A (FIG. 6). Moreover, the flange part 43 fits the outer side of the outer peripheral part of the upper support member 16 (FIG. 7).

  At this time, the height dimension H2 from the lower surface of the bolt fixing portion 44 to the lower end of the inner surface of the curved portion 47 is set to be smaller than the height dimension H1 of the step portion 41 (H2 <H1). The lower surface of the bolt fixing portion 44 of the cup 21 is spaced above the upper surface of the upper support member 16 in the dimension of H1-H2 (FIG. 7). Accordingly, when the bolt 20 is inserted into the bolt holes 42 and 46 and tightened and fixed, the cup 21 is deformed in a direction in which the bolt fixing portion 44 approaches the upper support member 16, and the bolt fixing portion 44 is eventually changed to the one shown in FIG. In this way, it is pressed against the upper surface of the upper support member 16. Therefore, the curved portion 47 of the cup 21 is pressed against the chamfered portion 41A of the step portion 41 of the upper bearing 16A, and seals between the cup 21 and the upper bearing 16A in a pressed state. The flange portion 43 is fitted to the outer peripheral portion of the upper support member 16 to seal this portion.

  In this way, the bending portion 47 is pressed against the chamfered portion 41A by tightening the bolt 20, thereby sealing between the center hole 21A of the cup 21 and the upper bearing 16A. Next, the curvature radius R of the bending portion 47 is sealed. The dimensions will be described with reference to FIG.

  In this figure, (a) shows a case where the radius of curvature R of the curved portion 47 is 1.6 mm, and the chamfer dimension C of the chamfered portion 41A is 0.3 mm. This is adopted in the above embodiment. Next, (b) shows the case where the radius of curvature R of the curved portion 47 is 3 mm and the chamfer dimension C of the chamfered portion 41A is 1.1 mm. In addition, in (b), t is the thickness dimension of the cup 21, and the steel plate of 0.8 mm is used in the Example. Further, φd indicates the diameter of the inner end of the stepped portion 41, which is φ26 mm in the embodiment. Further, φD indicates the diameter of the outer end of the stepped portion 41, which is φ28.2 mm in the embodiment. Accordingly, (φD−φd) / 2 is the overhanging dimension W of the stepped portion 41, which is 1.1 mm in the embodiment.

  FIG. 8C shows a case where the radius of curvature R of the curved portion 47 is 5 mm (the chamfered dimension of the chamfered portion 41A is the same as (b)), and FIG. 8D shows the radius of curvature R of the curved portion 47 of 10 mm ( (E) shows the case where the radius of curvature R of the curved part 47 is 20 mm (the chamfer dimension of the chamfered part 41A is the same as (b)). Show.

  It is difficult to make the curvature radius R equal to or less than the thickness dimension t of the cup 21. If the radius of curvature R is too large, the degree of adhesion between the curved portion 47 and the chamfered portion 41A cannot be maintained. Therefore, when the radius of curvature R increases as shown in FIG. 8E, the seal between the center hole 21A of the cup 21 and the upper bearing 16A cannot be maintained.

  According to experiments, it was confirmed that a sufficient sealing performance can be secured by setting the radius of curvature R of the curved portion 47 of the cup 21 within the range of t <R <10 * W. (A) to (d) in FIG. 8 fall within this range.

  As described above in detail, in the present invention, the upper bearing 16A of the rotary shaft 8 is provided on the upper surface and the upper support member 16 constituting the rotary compression element 3 and the upper bearing 16A penetrate the bolt on the upper surface of the upper support member 16. 20, a cup 21 that covers the upper surface of the upper support member 16 around the upper bearing 16 </ b> A and forms the discharge silencing chamber 19 is provided between the upper support member 16. A stepped portion 41 is provided in the upper bearing 16 </ b> A. The corner of the stepped portion 41 is chamfered to form a chamfered portion 41A, the inner edge of the cup 21 is bent with a predetermined curvature to form a curved portion 47, and the curved portion 47 is chamfered to the chamfered portion 41. The bolt fixing portion 44 of the cup 21 before being fixed to the upper support member 16 with the bolt 20 with the curved portion 47 being in contact with the stepped portion 41 while being in contact with the portion 41A is the upper support member. 6, the bolt fixing portion 44 of the cup 21 is fixed to the upper support member 16 with the bolt 20, whereby the curved portion 47 of the cup 21 is chamfered on the stepped portion 41 of the upper bearing 16. Press contact with the portion 41A.

  Due to the pressure contact between the curved portion 47 of the cup 21 and the chamfered portion 41A of the step portion 41, the sealing performance between the upper bearing 16A and the cup 21 is remarkably improved. The leakage of the refrigerant from the chamber 19 into the sealed container 2 can be effectively prevented or reduced. This makes it possible to reduce costs and reduce the defective rate during production while ensuring reliability.

  Further, by not using a separate part such as a ring, it becomes possible to make the tolerance in the height direction of the stepped portion 41 only the upper bearing 16A, and the amount when the refrigerant leaks between the chamfered portion 41A and the curved portion 47. The variation of the is also reduced. Furthermore, the pressing force of the curved portion 47 of the cup 21 against the chamfered portion 41A can be made constant over the entire circumference of the inner edge of the cup 21, so that the variation in distortion of the end surface of the upper bearing 16A can be reduced. .

  Further, the relationship between the radius of curvature R of the curved portion 47 of the cup 21, the thickness dimension t of the cup 21, and the overhang dimension W of the stepped portion 41 is t <R <10 * W. It becomes possible to reliably maintain the sealing performance between the chamfered portion 41 </ b> A and the curved portion 47 of the cup 21.

  In the embodiment, the description has been made using the hermetic rotary compressor having a single rotary compression element. However, the present invention is not limited to this, and a multi-cylinder having a plurality of rotary compression elements or a multistage hermetic rotary compressor. Even so, the present invention is effective.

DESCRIPTION OF SYMBOLS 1 Sealed rotary compressor 2 Sealed container 3 Rotation compression element 4 Electric element 7 Refrigerant discharge pipe 8 Rotating shaft 12 Cylinder 16 Upper support member (support member)
16A Upper bearing (bearing)
19 Discharge silencer 21 Cup 21A Center hole 26 Desuperheater outlet pipe 27 Desuperheater return pipe 41 Stepped portion 41A Chamfered portion 42, 46 Bolt hole 44 Bolt fixing portion 47 Curved portion

Claims (2)

An electric element and a rotary compression element driven by the rotary shaft of the electric element are housed in a sealed container, and after the refrigerant compressed by the rotary compression element is discharged into the discharge silencer chamber, an external desuper In a hermetic rotary compressor that flows into a heater, cools in the desuperheater, returns to the sealed container, and discharges from a refrigerant discharge pipe attached to the sealed container.
A support member having the bearing of the rotating shaft on one side and constituting the rotating compression element;
A cup that is fixed to one surface of the support member with a bolt so that the bearing penetrates, and that covers the one surface of the support member around the bearing and constitutes the discharge silencing chamber between the support member,
The bearing has a stepped portion, the corner of the stepped portion is chamfered to form a chamfered portion, the inner edge portion of the cup is curved with a predetermined curvature to form a curved portion, and the curved portion is the stepped portion. The bolt fixing portion of the cup before being fixed to the support member by the bolt in a state where the curved portion is in contact with the stepped portion and the chamfered portion of the cup is separated from the support member. A hermetic rotary compressor characterized by being dimensionally related.   2. When the radius of curvature of the curved portion of the cup is R, the thickness dimension of the cup is t, and the projecting dimension of the stepped portion is W, t <R <10 * W. The hermetic rotary compressor described.